Vertical vibration of an embedded flexible foundation in multi-layered transversely isotropic saturated soil

Abstract

The response of a circular foundation embedded in a multi-layered transversely isotropic poroelastic half-space under time-harmonic vertical loading is analyzed by treating the foundation as a classical plate and assuming the foundation-soil contact surface to be smooth and either permeable or impermeable. The displacement influence functions for multi-layered saturated soils, which are required for the present solution scheme, are obtained by employing an exact stiffness matrix method based on Biot’s poroelastic model and Hankel integral transforms. A variational approach based on the discretization of the contact surface and the displacement influence functions is used to formulate the dynamic soil-structure interaction problem. Selected numerical results portray the influence of excitation frequency, foundation flexibility and permeability, embedment, soil heterogeneity and depth of water on vertical vibrations of foundations. A sensitivity analysis is also presented to illustrate the impact of the key input parameters on the dynamic response.